Temperature regulating device



Nov. 13, 1945. v. WEBER TEMPERATURE REGULATING DEVICE Filed June 20, 1941 3 Sheets-Sheet 1 INVENTOR. VICTOR WEBER. ATTO RNE).

Nov. 13, 1945. v. WEBER 2,389,014

TEMPERATURE REGULATING DEVI CE INVENTOR. VICTOR WEBER BY m ATTORNEY Nov. 13, 1945. v. WEBER TEMPERATURE REGULATING DEVIC E' 5 Sheets-Sheet 3 Filed June 20, 1941 5 v .INVENTOR. VICTOR WEBER.

ATTORNEV.

Patented Nov. 13, 1945 TEMPERATURE REGULATING DEVICE Victor Weber, Greensbnrg, Pa., assignor to Robertshaw Thermostat Company, Yonngwood Pa., a corporation of Pennsylvania Application June 20, 1941, Serial No. 398,955

Claims. This invention relates to temperature regulating devices and, more particularly, to theme-- statically actuated devices for regulating the supply of heat to electric ovens and the like.

The ordinary electric range is provided with an element in the lower portion of the oven which is used primarily for baking purposes, and an element in the upper portion of the oven used primarily for broiling purposes. Thermostatic regulating devices have been provided to connect both elements simultaneously to a current source for preheating the oven and then automatically to disconnect the broiling element for conducting a baking operation. Such an arrangement is disclosed in my copending applications, Serial Nos. 247,390 and 323,162, now Patent Nos. 2,385,433 and 2,385,434, respectively.

In the structures described and shown in these applications a preheating operation followed by a baking operation can be conducted by manually operating the adjusting means by rotating its dial to connect both the broil and the bake elements to the line and immediately thereafter rotating the dial in a reverse direction to the desired baking temperature. If it is desired to conduct a baking operation without preheating, the dial is merely rotated to the desired baking temperature. If broiling alone is to be conducted then the dial is rotated to the highest temperature setting or broil position.

While this arrangement provides control of baking and broillng operations, together with rapid heating when desired, it is sometimes deirable to conduct a broiling operation at a lower temperature than is possible with the arrangement described. Thus, iood may be required to be broiled by operation of the oven at any set temperature within the high and low limits of such an operation. Also, iood which has been subjected to a baking operation maysubsequent ly be exposed to the heat of the trolling element for final cooking purposes while the oven remains at the halting temperature or is operated at any other selected temperature.

It is an object oi this invention to permit broiling operations to be conducted at any desired temperature while also providing for the rapid preheating oi the oven following by a baiting operation with a single setting of the con trol dial.

Another object oi the invention is to permit both baking and trolling operations to be com ducted at any desired temperature.

Another object oi the invention is to reset the oven regulating device automatically to a set optill crating position whenever the dial is turned to an 01! position.

Other objects and advantages will become apparent from the following description taken in connection with the accompanying drawings, wherein-- Fig. 1 is a front elevation 01' the temperature regulating device;

Fig. 2 is a top plan view of the structure shown in Fig. 1;

Fig. 3 is a side" elevation 01' the structure shown in Fig. 1;

Fig. 4 is a section taken along the line IV-IV of Fig. 2 looking in the direction indicated by the arrows;

Fig. 5 is a section taken along the line V-V of Fig. 1 looking in the direction indicated by the arrows;

Fig. 6 is a section taken along the line VI-VI of Fig. 1 looking in the direction indicated by the arrows;

Fig. 7 is a section taken along the line VII-VII of Fig. 5 looking in the direction indicated by the arrows;

Fig. 8 is a section taken along the line VIII- VIII of Fig. 6 looking in the direction indicated by the arrows;

Fig. 9 is a wiring diagram showing the electrical connections for the structure;

Fig. 10 is a side view oi the adjust dial;

Fig. 11 is a front elevation of the adjusting dial shown in Fig. 10.

Fig. 12 is a front view similar to Fig. i but with the dial removed;

Fig. 13 is a section taken on the line .A -mr of Fig. 12 looking in the direction indicated by the arrows; and

Fig. 14 is a perspective View of the parts shown in section in Fig. 13.

In the embodiment shown in the drawings, the operating levers of the regulating device are mounted in a main housing 2 and in a rearhous-= ing 3 which is carried by the main housing 2.

of the screw engages the usual stud attached to an expansible and contractible diaphragm d to sup art and move the diaphragm.

The interior .of the diaphragm 9 is in communication with a capillary tube it which, in turn, is in communication with the interior of the temperature sensitive bulb (not shown) which is positioned in the, oven or other chamber, the temperature of which is to be controlled. A contractible and expansible liquid is provided in the bulb and the capillary tube id so that upon expansion of the liquid as a result of the heat to which the bulb is subjected, the liquid will be forced through the tube into the expansible and contractible diaphragm s, thereby actuating the diaphragm to a suiiicient extent to operate the parts to be described for shutting off or turning on the supply of current to the oven. A tip it is provided on the face of the diaphragm opposite the stud to facilitate the transmission of the expansive forces of the diaphragm to the parts to be described.

The tip it abuts a button M in the recessed portion H of a main operating lever it. The operating lever it has a knife edge i! at its upper end seated in V-shapedbearings 98 in a bracket is which is secured to the rear wall 52 of the main housing.

The lower end of the main operating lever I6 is U-shaped to provide a space between its legs for the, reception of a tension spring 2!. The lower end of the main operating lever is provided with a knife edge 22 which cooperates with one ,."-gend of the tension spring 2|. The upper end of the tension spring 2! extends through an opening 23 in an R-shaped secondary operating lever or contact a m 24. The opening 23 is provided with a knife edge 25 for cooperation with the spring, so that there will be relatively little or no friction to afiect the operation of the structure.

Each leg 26 of the secondary lever or contact arm 24 has a knife edge 21. The knife edges 27 rest in V-shaped bearings 25 formed; in a bracket 29. The rear end of the bracket 29 is provided with arms 30 which extend slightly through and are supported by the rear wall l2 of the mainhousing. The front end of the bracket 29 is provided with a screw 3!, the bottom end of which rests on the bottom of the main housing. This screw can be threaded through the bracket so as to raise or lower it and thereby eilect an adjustment of the operating range of the levers. The secondary lever 24 is provided with an opening 32 so as to permit the tip H carried by the diaphragm to extend past it and to contact the button l4 carried by the main operating lever.

A take-up arm 38 of inverted U-shape in general configuration is provided for cooperation with the secondary lever or contact arm 24. The legs 39 of the take-up arm are provided at their lower ends with projections or bearings 40 which extend outwardly from the general plane of the take-up arm and rest on inwardly projecting ledges or bearings 41 formed on the contact arm 25. The upper end of the take-up arm 38 extends above the upper end of the contact arm 24 and carries an insulating bar 42. This insulating bar is mounted on the upper end of the takeup arm in such away as to permit a slight pivoting in a horizontal plane to facilitate the slimment of contact bridges 43, which are carried by the insulating bar. The contact bridges 43 cooperate with the contacts 44, 45-, 46 and 41 which are supported on an'insulating block 48 carried by the rear wall I 2 of the main housing. The conaeaaoie tacts Stand ii are connected to a source of power through the lines it as shown in Fig. 9. The block dd also supports an insulating plate 59 l which extends downwardly behind the take-up abuts a washer arm 8B and limits the movement thereof in a contact breaking direction.

The take-up arm 38 is provided with a hook 50 which extends around the underside of the top cross-piece of the R-shaped contact arm 24. This hook E9 limits the movement of the take-up arm in respect to the contact arm 24. A spring normally urges the take-uparm toward the contact arm. One end of the spring abuts the rear face of the take-up arm and the other end 52 on a stud 53 projecting from the upper end of the contact arm.

It will be seen from the above description that, as the liquid inthe bulb and in the capillary tube it expands in response to the temperatures preveiling in the oven, the diaphragm 9 ,will expand and will force the lower end of the thermostatically actuated lever it past the pivot point of the contact arm 2%. Due to the spring tension the contact arm and the take-up arm will be moved to the left as viewed in Fig. 5, thus breaking the contact between the-contact bridges 43 and the contacts M, 45, 66 and 4'! to interrupt the flow of current from the power lines M.

So long as the diaphragm 9 remains in the expanded position, the current will be interrupted,

but upon cooling down of the oven the diaphragm will contract and, as soon as the lower end ofthe lever lfi passes the pivot point in the other direction, the contact arm 24 and the take-up. arm will be moved to the right as viewed in Fig. 5,

and the current will again be permitted to passings 5! in the forwardly extending legs 62 of a 7. ing laterally out of I bracket at secured to the rear wall l2 of the main housing. The legs 62 extend horizontally beyond the openings 6i and beyond the legs of the broil lever 58 and their outer ends are positioned adjacent the legs 26 of the contact arm 24. In this manner, the legs 25am prevented from slidthe bearings 28.

The arm $3 of the broil lever is provided with a tapered depression 55 which cooperates with a cone-shaped disk 65. One end of a spring 61 abuts the disk 65 and the other end of this spring carries a similar disk 68 which cooperates with a depression 69 in a bracket Ill carried by the rear wall of the main housing. The spring 61 is normally under compression and, consequently, will maintain the broil lever E8 in any position to which it is moved on either side of the pivot on which it is mounted. When'the upper end of the broil, lever is moved past the pivot point to the right, as viewed in Fig. 5, the spring arrangement just described will Operate to snap the contact bridge 55 into engagement with the contacts 54 and 540 so as to permit current to pass to the broil element. It the broil lever is moved to the left, a viewed in Fig. 5, a sufilcient distance to pass the pivot point then the spring arrangement will serve to hold the broil lever away from the contacts 54 and 54a, thus maintaining in an inarm I59 of the broil lever.

' thereof in any desired manner, as will now be explained. I

An operating link 'II is plvotally mounted on a resetting link 12 at Ila. The resetting link 12 -is provided with horizontally extending arms 13 which are provided with openings 14 cooperating with a pivot pin 15 carried by a bracket 16 which, in turn, is carried by the-rear wall I2 of the main housing. The operating link H is provided with laterally extending spaced arms TI normally extending between the'broil lever 58 and the contact arm 24. The resetting link 12 i normally forced toward the .contact arm and the broil lever by a spring 18, one end of which .abuts the bracket 16. The distance between the arms 11 of the operating link is approximately the same as the distance between the adjacent faces of the contact arm 24 and the broil lever 88 when the contact bridges 48 and i engage their respective contacts.

I! the broil lever is in the position where the contact bridge therefor engages its contact and the temperature in the oven reaches the desired setting, the movement of the contact arm 24 causing movement of the main bridges 43 away from their respective contacts will also operate, through the operating link 'H, to move the broil lever to a position where the contact arm carried thereby is disengaged from the contacts 54 and 54a. The broil lever 88 will then remain in that position until manually moved into engagement with its contacts.

The broil lever i manually moved into a position to establish the broil circuit by means of the resetting link I2 and a reciprocable member in the form of an operating bar 80. The resetting link H has a horizontally extending arm 8| thereon which is adapted to cooperate with a cupshaped projection 82 carried on the rear face of As the resetting link is rocked on its pivot the arm 8| engages the cupshaped projection 82 and slides along the face thereof to force the broil lever into its forward position where the contact bridge 55 engages the contacts. The resetting link isfurther provided with an car 83 which cooperates with a sloping surface 84 on the operating bar '80. As this bar is pushed inwardly, by rotation of the dial, the face 84 slides over the ear 83 and rocks the resetting link on its pivot, thereby forcing the broil lever forward. By virtue of the toggle arrangement de-' scribed above, the broil lever will remain in this position until moved therefrom.

If the operating bar 8015 held in, as described,

the resetting link 12 and the operating link 1i carried thereby will be held in their outer position. In this position the terminal end portions of the arms 11 of the operatin link will still be between the contact arm 24 and the arm 59 of the broil lever, the arms of the operating link being made sufliciently long for this purpose. In this position, the contact arm 24 can be actuated by the diaphragm and the actuating lever without moving the broil lever from closed position. The terminal ends of the arms 11 of the operating link are spaced sufflciently far-apart to permit movement of the contact without corresponding movement oi the broil lever. The contact arm can therefore be actuated so as to break the circuit without disturbing the contact between the bridge 88 and the contacts 84 and 84a.

If the operating bar is released after having been pushed in so as to move the broil lever into contact position, the spring 19 will force the resetting llnk, the bar 80 and the operating link ll back into normal position. A flat spring 80a extends from the outer surface of the housing into a slot formed in the bar so and assists in retuming it to normal position. If the diaphragm thereafter moves the contact arm 24 in response to an increase in temperature the movement of the contact arm will cause the broil lever 88 to move in a direction to disengage bridge 55 from contacts 84 and 54a and thus break the broil circuit.

The rear housing 3 contains the contacts for the bake element circuit. As shown in Fig. 4, contacts 88 are mounted on contact arms 81 connected with terminals 88 and 88a extending from the rear housing. The contacts 86 cooperate with contacts 89 and 89a which are carried by the rear housing and which, through appropriate connections to be described hereinafter, are connected to the contacts 45 and 4B which are connected to the power source through the contact bridges 48. The contacts 86 are normally in contact with the contacts 89 and 89a. When it is desired to separate these contacts they are moved manually apart in a manner to be described.

The end of the operating arm 80 engages a pin 90 extending from the main housing into the rear housing. The other end of the pin 90 engages an insulating block 9| which bears against the arms 81. This insulating block 9| is loosely supported on an insulating pin 92 carried by the rear housing. As the arm 80 is moved rearwardly it moves the pin 90 rearwardly and effects a separation of the contacts. so that, regardless of whether the contact bridges 43 are in engagement with their respective contacts, no current will flow to the bake element. This condition prevails only when the adjusting dial 1 is turned to the high position at which the operating arm 80 is moved rearwardly or when the arm 80 is otherwise moved rearwardly. When the dial I is turned to the high position a cam member 98, which is carried on the rear face of the dial, cooperates with the operating bar or arm 80 and moves it rearwardly. As soon as the adjusting dial 1 is turned away from the position in which the cam 98 moves the arm rearwardly, the bake circuit through the contacts just described will be reestablished, although whether current flows to the bake element depends also upon the position of the contact bars 43.

- If the broil lever is in its rear position when the adjusting dial is turned to the high" position the operating arm 80 not only opens the contacts in the bake circuit in the manner just described, but it also moves the broil lever to forward position where the contact bridge 55 comes into engagement with the contacts 54 and 54a. If the adjusting dial is turned back toward the off position the contacts in the bake circuit will again close, as the arm will be moved forward by the spring 79, and the contact bridge 55' will remain in contact with the contacts 54 and 56a. When in this position a preheating operation can be carried on. Additional contacts are carried in switching a bracket I01 having an upwardly extending arm I08 secured thereto. A compression spring I09 extends between the arm I08 and arm I05 and normally forces the contact bridge I04 into engagement with contacts I and I02. A pin III extends between insulated extension 56 of the broil lever and a rearwardly extending arm II2 carried by the contact arm I05, a hole being provided in the contact arm I to permit the pin to extend therethrough. As the broil lever is moved to a position to disengage the contact bridge 55 and contacts 54 and 54a, the pin III moves the bridge H04 away from the contacts I00 and I02.

It should be noted that as the dial is rotated from the ofi" position to a point just above the 550' mark, the dial does not move the bar 80 at all. If the dial is moved to the high position, then the end of the bar 80 slides along the sloping face of th cam member 90. The movement of the bar 00 by the cam operates the broil lever and the bake contact pin 90 in the manner just described. A projection. 91 is provided on the cam to prevent the dial from being rotated past the high setting to the o position. The "ofl position can be reached only by rotating the dial in a counter-clockwise direction. The side of the cam 98 opposite the sloping face forms a stop 96 and prevents rotation of the dial past the off position when. rotated in a counterclockwise direction.

1 This invention is more particularly directed toward the provision of means for connecting the broil element circuit to the current supply independently of rotation of the adjusting dial. To this end, separate means for actuating the bar cisely the same as if it had been moved by the cam 03 on the. dial 1.

Means are provided to return the auxiliary operating means for the bar 80 to inactive position whenever the main dial 1 is moved to "off" position. An abutment I2'I projects from the collar II! on the. opposite face to the raised portionII'I. A bracket I20 secured to the front cover 4 is provided with a projecting lug I30 which carries a rod I29 adapted for slidable movement relative thereto. The rod I29 extends di-- agonally between the abutment I21 and the stop 80'is provided. The main housing 2-is provided on the side adjacent the bar 80 with .a bracket having a pair of spaced ears H3 supporting a slidable and rotatable shaft 4 exterior of the housing. Secured to the shaft beyond the ears H3 is a flanged collar ilfi-forming a' cam element having a sloping face H0 adjoining a flat raised portion III which terminates on the other end in a stop H8. The shaft "6 further carries an operating member M9 for the bar 80 whichis slidable thereon against the pressure of a coil spring I20 operative between the member H9 and the adjacent ear I I8. .The shaft is retained against withdrawal from the bracket by a pin i24 extending transversely through the end of the shaft projecting beyond the ears.

The operating member H9 comprises a fiat collar carried on a bushing I26 and having a lug Iii projecting from its edge. An arm 122 extends from the operating member 9 to support an operating finger I23. The finger extends into a slot I24 formed in the bar 80in front of the spring 800:. The projecting end of the shaft H4 is provided with a handle H25 suitably marked with the word "Broil. Thus, when the shaft is 1'0- tated counterclockwise the sloping face of the flange engages the adjacent lug I2I and pushes the operating member inwardly, compressing spring I20 and moving bar 80 longitudinally through the medium of the finger I23. The flat portion III engages lug I2I and serves as a holdposition. The operation of the bar 80 is pre- 96 on the dial i. Thus, the stop 98 moves the rod longitudinally in one direction while the abutment I2I moves it in the other. In this manner, when the dial is moved from "011 position and the auxiliary handle I25 is operated to move the bar 80, the abutment I2'I simultaneously moves the rod 520 into position to be reverseiy moved by the stop 06 when the dial is again brought to off position. Such reverse movement of the rod l29 will serve to rotate the shaft II4 permitting the operating member M9 to slide longitudinally down the sloping face H6 and thus return the bar 00 to its normal position.

If it is desired to operate the bake element only, the adjusting dial is turned from the fofi position to the desired temperature, say, 400. Rotation of the dial will not operate to close the broil switch as the dial is not moved sufliciently far to accomplish this. The main thermostat switch will, however, close and as the contacts 86 and 09, 09a of the bake switch are normally closed, current will be supplied from the current source l0 to the bake element until the temperature reaches 400. The diaphragm will then have exl panded to a suflicient extent to operate the thermostatic lever it to cause the contact arm to operate the main thermostat switch and break the circuit. When the temperature of the compartment or oven drops to slightly below 400 the contraction of the diaphragm will then function to close the main thermostat switch. During an thermostat switch and the broil switch. It also operates to open the bake switch. Immediately after turning the dial to the high position the operator turns the dial back to the desired temperature setting, say, 400. The rotation of the dial back to this point does not disturb the broil switch but it does permit the switch in the bake circuit to close and reestablish the bake circuit. The broil switch, the bake switch, and the main thermostat switch are all closed and the heating will continue 'until the desired temperature of 400 is reached. The expansion of the diaphragm will operate to open the main thermostat switch and the movement thereof will also function to open the broil switch. The bake switch is not operated at this time but remains closed. However, the current through the bake element has been interrupted by the opening of the main thermostat switch and current will not again be supplied to the bake element until the temperature drops to just below 400, at which time the thermostat switch will close.

If it is desired to perform this preheating but to substitute low temperature broiling as the subsequent operation the adiusting dial is moved again to the high" position and back to the desired temperature setting. As previously stated. the broil switch, bake switch and main thermostat are now closed. To open the bake switch the auxiliary handle it! is operated. moving bar 80 inwardly for this function. Thus, the broil switch will operate under thermostat control after the preheating period.

It is often desirable to conduct a broiling opera ation at the same or a diflerent temperature to a previous baking operation while the food remains in the oven. It may also be desirable to conduct a broiling operation at any temperature without a previous baking operation. with the device or this invention such operations are readily carried on. All that is required is to operate the auxillary handle I25 while the dial 1 remains at, or is moved to, any desired temperature setting. Such operation will open the bake switch and close the broil switch which remains under control of the thermostat. When the dial I is returned to "oil" position the stop on the back thereof will actuate the mechanism described to return bar Bil to normal position and open the broil switch.

I claim:

1. A temperature regulating device for an electric oven and the like comprising a broil element and a bake element adapted to be energized from a source oi current supply through switches, said device comprising a thermostat for controlling the operation of said switches in accordance with the temperature of the oven, manual means movable to diflerent temperature settings for adjusting said thermostat for preheating the oven and thereafter conducting a baking operation, said elements being connected simultaneously to the current supply by said manual means and said broiling element being thereafter disconnected by operation of said thermostat, said means including a control handle movable from "oil position through a maximum position to a baking temperature setting and an operating bar actuated thereby for closing the broil element switch, and auxiliary manual means for actuating said operating bar for closing said broil element switch for conducting a broiling operation while said control handle remains at said baking temperature setting.

2. A temperature regulating device for an electric oven and the like comprising a broil element and a bake element adapted to be energized from a source of current supply through switches, said device comprising a thermostat for controlling the operation of said switches in accordance with the temperature or the oven, manual means 7 movable to different temperature settings for adjusting said thermostat for preheating the oven and thereafter conducting a, baking operation,

said elements being connected simultaneously to the current supply by said manual means and said broiling element being thereafter disconnected by operation of said thermostat, said means including a control handle movable'from "oil" position through a maximum position to a baking temperature setting and an operating bar actuated thereby for closing the broil element switch, auxiliary manual means for actuating said operating bar for closing said broil element switch for conducting a broiling operation while said control handle remains at said baking temperature setting. and interengaging means between said control handle and bar for moving said auxiliary means to open the broil switch when said handle is operated to 08" position.

3. A temperature regulating device for electric ovens and the like having broil and bake elements energized from a source oi! current supply, said device comprising common switch mechanism for controlling energizationoi the elements, separate switch mechanism ,ior controlling energizetion of the broil element, separate switch mechanism for controlling energization of the bake element. said broil element being energizable in the operated condition of said broil switch mechanism and said bake element being energizable in the unoperated condition of said bake element switch mechanism, a thermostat for operating said common switch mechanism and causing alternate energizing and deenergizing of the elements to maintain selected oven temperatures, means for adjusting said thermostat to cliflerent temperature settings, means for operating both said separate switch mechanisms to the operated condition to cause energization of the broil element and simultaneous deenergization 01 the bake element, means efiective upon said operation of the switch operating means for maintaining said broil element switch mechanism in the operated condition, means carried by said adjusting means and effective in one position of said adjusting means and operatively engageable with said switch operating means for causing said operation thereof, means efiective in another position of said adjusting means for returning said bake element switch mechanism to its unoperated condition without afiecting said maintaining means and thereby permitting simultaneous energization of the elements, means for connecting said broil switch mechanism and said common switch-mechanism and rendering the latter effective upon deenergizing operation of said thermostat to overcome said maintaining means and cause operation of said broil element switch mechanism to unoperated condition, whereby energization of the bake element alone will occur upon subsequent energizing operation of said thermostat while said adjusting means remains in said other position, and adjusting means separate from said thermostat adjusting means and. operatively engageable with said switch operating means for causing said operation thereof whenever said thermostat adjusting means is in said other position, whereby either of the elements may be separately energized to conduct bake or broil operations preceded selectively by a preheating operation if said simultaneous energization of the elements is initiated.

4. A temperature regulating device for electric ovens and the like having broil and bake elements energized from a source of current supply, said device comprising common switch mechanism for controlling energization of the elements, separate switch mechanism for controlling energization of the broil element, separate switch mechanism for controlling energization of the bake element, a thermostat for operating said common switch mechanism and causing alternate energizing and deenergizing of the elements to maintain selected oven temperatures, means for ad justing said thermostat to different temperature settings, connecting means for operating said broil switch mechanism from said common switch mechanism upon deenergizing operation of said thermostat, means for displacing said connecting means and causing operation of said broil switch mechanism for energlzation of the broil element displacing means also causing operation of said bake switch mechanism for deenergization or the bake element concomitantly with said energizetion of the broil element, means effective in one position of said adjusting means for operating said displacing means. biasing means for returning said bake element switch mechanism to its unoperated condition in another position of said adjusting means for simultaneous energization of the elements, adjusting means separate irom 6. A temperature regulating device for electric ovens and the like having broil and bake elements energized from a source current supply. said device--comprising common switch mechanism tor controlling energization of the elements, separate switch mechanism for controlling energizetion of the broil element, separate switch mechanism for controlling energization of the bake said thermostat adjusting means for operating a said displacing means whenever said thermostat adjusting means is in said other position, and

a holding means for said separate adjusting means to continue energization of the broil element and deenergization of the bake element under thermostat control.

5. A temperature regulating device for electric ovens and the like having broil and bake elements energized from a source of current supply, said device comprising bake switch mechanism biased to closed position, broil switch mechanism having an initial open position, toggle m'eans ior maintaining said broil switch mechanism in the position to'which it is moved, means engageable with said switch mechanisms for joint operation thereof to reverse said positions, a thermostat operable Ior opening said broil switch mechanism, means for adjusting said thermostat and operable in one position .for actuating said switch engaging means, said bake-switch mechanism being closed under its bias in another position of said adjusting means and said broil switch mechanism being opened by said thermostat. a second adjusting means separate from said thermostat adjusting means, means movable by said second adjusting means ,for actuating said switch engaging means when said thermostat adjusting means is in said other position, holding means associated with said movable means for retaining said switch adjusting means in actuated position to continue element, a thermostat for operating said common switch mechanism and causing alternate energizing and deenergizing of the elements to maintain-selected oven temperatures, means for adjusting said thermostat-to diiierent temperature settings, connecting means for operating said broil switch mechanism from said common switch mechanism upon deenergizing operation of said thermostat, a reciprocable member engageable with said connecting means for displacement thereof and for causing operation of said broil switch mechanism for energization of the broil element irrespective of said thermostat operation, means for operating said bake switch mechanism for deenergization oi the bake element by movement of said reciprocable member, operating means carried by .said adjusting means for :moving said reciprocable member in one position of saidadjusting means, said reciprocable member being ineffective to displace said connectingmeans in another position 0! said adjusting means and permitting return or said bake switch mechanism to unoperated condition and control oi said broil switch mechanism by said thermostat, a second operating means for causing said movement of said re'ciprocable member when said thermostat adjusting means is in said other position, a cam element engageable with said second operating means for operating the same, adjusting means separate irom said thermostat adjusting means tor moving said cam into and out of engagement with said second operating means, and holding means associated with said cam element for retaining said operating means in said operated position and thereby said reciprocable member in its moved position to continue deenergization of the bake element and energization oi the broil element under thermostatic control.

VICTOR WEBER. 

